Tiva Timer: Timer test must attach a timer handler or the timer is stopped at the first interrupt

3 files changed, 60 insertions, 23 deletions

diff --git a/apps/examples/timer/timer_main.c b/apps/examples/timer/timer_main.c
index ed1219447..4546e5b9d 100644
--- a/apps/examples/timer/timer_main.c
+++ b/apps/examples/timer/timer_main.c
@@ -72,6 +72,21 @@
  ****************************************************************************/
 
 /****************************************************************************
+ * timer_handler
+ ****************************************************************************/
+
+static bool timer_handler(FAR uint32_t *next_interval_us)
+{
+  /* This handler may:
+   *
+   * (1) Modify the timeout value to change the frequency dynamically, or
+   * (2) Return false to stop the timer.
+   */
+
+  return true;
+}
+
+/****************************************************************************
  * timer_status
  ****************************************************************************/
 
@@ -111,6 +126,7 @@ int main(int argc, FAR char *argv[])
 int timer_main(int argc, char *argv[])
 #endif
 {
+  struct timer_sethandler_s handler;
   int ret;
   int fd;
   int i;
@@ -144,6 +160,28 @@ int timer_main(int argc, char *argv[])
       return EXIT_FAILURE;
     }
 
+  /* Show the timer status before attaching the timer handler */
+
+  timer_status(fd);
+
+  /* Attach the timer handler
+   *
+   * NOTE: If no handler is attached, the timer stop at the first interrupt.
+   */
+
+  printf("Attach timer handler\n");
+
+  handler.newhandler = timer_handler;
+  handler.oldhandler = NULL;
+
+  ret = ioctl(fd, TCIOC_SETHANDLER, (unsigned long)((uintptr_t)&handler));
+  if (ret < 0)
+    {
+      fprintf(stderr, "ERROR: Failed to set the timer handler: %d\n", errno);
+      close(fd);
+      return EXIT_FAILURE;
+    }
+
   /* Show the timer status before starting */
 
   timer_status(fd);
diff --git a/nuttx/arch/arm/src/sam34/sam_tc.c b/nuttx/arch/arm/src/sam34/sam_tc.c
index 1f866726a..0f2ae3c37 100644
--- a/nuttx/arch/arm/src/sam34/sam_tc.c
+++ b/nuttx/arch/arm/src/sam34/sam_tc.c
@@ -276,7 +276,9 @@ static int sam34_interrupt(int irq, FAR void *context)
     {
       uint32_t timeout;
 
-      /* Is there a registered handler? */
+      /* Is there a registered handler?  If the handler has been nullified,
+       * the timer will be stopped.
+       */
 
       if (priv->handler && priv->handler(&priv->timeout))
         {
@@ -291,9 +293,12 @@ static int sam34_interrupt(int irq, FAR void *context)
           timeout = (1000000ULL * priv->clkticks) / TC_FCLK;    /* trucated timeout */
           priv->adjustment = (priv->adjustment + priv->timeout) - timeout;  /* truncated time to be added to next interval (dither) */
         }
-      else /* stop */
+      else
         {
+          /* No handler or the handler returned false.. stop the timer */
+
           sam34_stop((FAR struct timer_lowerhalf_s *)priv);
+          tcvdbg("Stopped\n");
         }
 
       /* TC_INT_CPCS is cleared by reading SAM_TCx_SR */
diff --git a/nuttx/arch/arm/src/tiva/tiva_timerlow32.c b/nuttx/arch/arm/src/tiva/tiva_timerlow32.c
index ab6053db2..20bf600a8 100644
--- a/nuttx/arch/arm/src/tiva/tiva_timerlow32.c
+++ b/nuttx/arch/arm/src/tiva/tiva_timerlow32.c
@@ -87,7 +87,7 @@ struct tiva_lowerhalf_s
 
 static uint32_t tiva_usec2ticks(struct tiva_lowerhalf_s *priv, uint32_t usecs);
 static uint32_t tiva_ticks2usec(struct tiva_lowerhalf_s *priv, uint32_t ticks);
-static int      tiva_timeout(struct tiva_lowerhalf_s *priv, uint32_t timeout);
+static void     tiva_timeout(struct tiva_lowerhalf_s *priv, uint32_t timeout);
 
 /* Interrupt handling *******************************************************/
 
@@ -192,11 +192,11 @@ static uint32_t tiva_ticks2usec(struct tiva_lowerhalf_s *priv, uint32_t ticks)
  *   timeout - The new timeout value in microseconds.
  *
  * Returned Values:
- *   Zero on success; a negated errno value on failure.
+ *   None
  *
  ****************************************************************************/
 
-static int tiva_timeout(struct tiva_lowerhalf_s *priv, uint32_t timeout)
+static void tiva_timeout(struct tiva_lowerhalf_s *priv, uint32_t timeout)
 {
   timvdbg("Entry: timeout=%d\n", timeout);
 
@@ -215,8 +215,6 @@ static int tiva_timeout(struct tiva_lowerhalf_s *priv, uint32_t timeout)
 
   timvdbg("clkin=%d clkticks=%d timeout=%d, adjustment=%d\n",
           priv->clkin, priv->clkticks, priv->timeout, priv->adjustment);
-
-  return OK;
 }
 
 /****************************************************************************
@@ -246,7 +244,9 @@ static void tiva_handler(TIMER_HANDLE handle, void *arg, uint32_t status)
     {
       uint32_t timeout;
 
-      /* Is there a registered handler? */
+      /* Is there a registered handler?  If the handler has been nullified,
+       * the timer will be stopped.
+       */
 
       if (priv->handler && priv->handler(&priv->timeout))
         {
@@ -269,9 +269,12 @@ static void tiva_handler(TIMER_HANDLE handle, void *arg, uint32_t status)
           timeout = tiva_ticks2usec(priv, priv->clkticks);
           priv->adjustment = (priv->adjustment + priv->timeout) - timeout;
         }
-      else /* stop */
+      else
         {
+          /* No handler or the handler returned false.. stop the timer */
+
           tiva_timer32_stop(priv->handle);
+          timvdbg("Stopped\n");
         }
     }
 }
@@ -422,7 +425,6 @@ static int tiva_getstatus(struct timer_lowerhalf_s *lower,
 static int tiva_settimeout(struct timer_lowerhalf_s *lower, uint32_t timeout)
 {
   struct tiva_lowerhalf_s *priv = (struct tiva_lowerhalf_s *)lower;
-  int ret;
 
   DEBUGASSERT(priv);
 
@@ -435,15 +437,12 @@ static int tiva_settimeout(struct timer_lowerhalf_s *lower, uint32_t timeout)
 
   /* Calculate the the new time settings */
 
-  ret = tiva_timeout(priv, timeout);
-  if (ret == OK)
-    {
-      /* Reset the timer interval */
+  tiva_timeout(priv, timeout);
 
-      tiva_timer32_setinterval(priv->handle, priv->clkticks);
-    }
+  /* Reset the timer interval */
 
-  return ret;
+  tiva_timer32_setinterval(priv->handle, priv->clkticks);
+  return OK;
 }
 
 /****************************************************************************
@@ -584,12 +583,7 @@ int tiva_timer_register(const char *devpath, int gptm, uint32_t timeout,
 
   /* Set the initial timer interval */
 
-  ret = tiva_timeout(priv, timeout);
-  if (ret < 0)
-    {
-      timdbg("ERROR: Failed to set initial timeout\n");
-      goto errout_with_alloc;
-    }
+  tiva_timeout(priv, timeout);
 
   /* Create the timer handle */